Hand wire stripper



July 8, 1958 H. R. WATSON 'HAND WIRE STRIPPER Filed May 24, 1957INVENTOR.

HA'QOLD 2. 14/4 T30,

' qrroe/vevs.

United States Patent Ofiice 2,342,017 Patented July 8, 1958 HAND WIRESTRIPPER Harold R. Watson, Victorville, Calif.

Application May 24, 1957, Serial No. 661,359

4 Claims. (Cl. 81--9.5)

This invention relates to tools and, more specifically, the presentinvention pertains to manually operated tools for extracting a wire froma shielded cable.

One of the primary objects of this invention is to provide a hand toolfor terminating the metal woven shield of a jacketed conductor or wireof the type generally utilized in electrical installations.

Another object of this invention is to provide a hand tool of the typereferred to above for terminating the metal woven shield of a jacketedconductor, an operaion known in this art as pigtailing, without frayingthe stranded shielding and without damaging the insulalion of the wire.

A further object of this invention is to provide a hand tool asdescribed above, the tool being noncomplex in construction and assembly,inexpensive to manufacture, and durable in use.

Other and further objects and advantages of the present invention willbecome more manifest from a consideration of the following specificationwhen read in conjunction with the annexed drawing, in which:

Figure 1 is a top plan view of the hand tool constructed in accordancewith the teachings of the present invention;

Figure 2 is a longitudinal cross sectional view of the tool shown inFigure 1, taken on the horizontal plane of line 2-2 of Figure 1, lookingin the direction of the arrows;

Figure 3 is a front elevational view of the tool; and

Figure 4 is a detailed cross sectional view, partly in elevation, takenon the vertical plane of line 4-4 of Figure 2, looking in the directionof the arrows.

Referring now more specifically to thedrawing, reference numeraldesignates a hand tool constructed in accordance with the instantinvention. As illustrated, the tool 10 includes an elongated bulboushandle member 12 having a forwardly extending neck portion 14 of reduceddiameter. The neck portion 14 is provided with an elongated axiallyextending bore 16 which terminates at its inner end in a second bore 18of reduced diameter. The bore 18 receives therein the inner end of anelongated rod 20 which projects therefrom through and beyond the forwardend of the neck 14. One end of an elongated substantially hollow tubularelement is inserted within the bore 16 in concentric relation relativeto the rod 20. As is seen in Figures 1 and 2, the tubular element 22projects beyond the forward end of the neck 14 for a distance shorterthan the longitudinal axis of the rod 20. The reference numeral 24designates an elongated helicoidal spring which is disposed within thehollow tubular element 22. As is clearly seen in Figure 2 of thedrawing, one end of the helicoidal spring 24 abuts against the inner endof the bore 16, and the other end of the spring 24 engages against theoutwardly turned radial flange 26 carried on the inner end of anelongated substantially hollow tubular member 28. For reasons to becomemore apparent below, the tubular member 28 is mounted for reciprocationon the rod 20. The other or outer end of the tubular member 28 is cutaway to form an arcuately shaped wall 30 which terminates in a point 32.

The helicoidal spring 24 is under compression and thus constantly tendsto urge the tubular member 28 for movement in a direction away from thehandle 14. To prevent the displacement of the tubular member 28 fromwithin the hollow tubular element 22, a cylindrical sleeve 34 is pressfit within the outer orforward end of the tubular element 22. The flange26 abuts against the inner end of the sleeve 34 when the tubular member28 is in its furthermost extended position.

To prevent damage to the forward end of the neck 14,

a cap 36 having a central aperture 38 is mounted thereover, the aperture38 receiving the elongated tubular element therethrough.

Having described the tool of the present invention in detail theoperation thereof is set forth below.

As is Well known in the art, most shielded conduits are provided with anouter shield beneath which is positioned a woven metallic shield. Thewoven metallic shield encases the wire insulating material. Now when itbecomes necessary for terminating the shield, the outer shield is cutback from one end of the conductor to the desired point. Thereafter, thepointed end 32 of the tool 10 is inserted between the insulatingmaterial and the woven metallic shield, the arcuate wall Y30 and theforward end of the tubular member 28 receiving therein the conductor andthe insulating material immediately adjacent thereto. As the wire andits associated insulation is received within the tubular member 28, thewire or conduit will engage against the outer end of the rod 20.

In carrying out these operations, it is preferable that the arcuate wall30 be disposed on the upper side of the conduit. With the tool in thisposition, the operator now bends the tool 10 downwardly causing thepointed end 32 to penetrate through the woven metallic shield.

The operator now grasps the hollow tubular member 28 between his fingersand rotates the tubular member 28 around its longitudinal axis therebyenlarging the penetration of the woven metallic shield. After theopening made by the penetration is large enough to receive therethroughthe conductor and its insulator, the operator now holds the tubularmember 28 stationary and moves the handle member toward the pointed end.This causes the rod 20 to move relative to the tubular member 28 therebyforcing the conductor outwardly of the tubular member 28 and expels thesame through the opening formed in the metallic woven shield.

Having described and illustrated one embodiment of this invention indetail, it will be understood that the same is oifered merely by way ofexample and that the invention is to be limited only by the scope of theappended claims.

What is claimed is:

1. A hand tool for pigtailing a shielded conductor comprising anelongated hollow tubular member having an end portion thereof cut awayand terminating in a point, a rod mounted for reciprocation within saidtubular member, said rod having one of its ends projecting beyond theother end of said tubular member and its other end being normallydisposed within said tubular member adjacent to but spaced from saidpointed end, and resilient means constantly tending to urge said rod andtubular member for movement away :from each other.

2. A hand tool for pigtailing a shielded conductor comprising a handlehaving one end of an elongated rod fixedly secured thereto, an elongatedtubular member having a pointed end and mounted for reciprocation onsaid rod, resilient means carried on said handle and engaging the otherend of said tubular member, said resilient means constantly tending tourge said tubular member for relative movement away from said handle,and means for limiting said movement.

3. A hand tool as defined in claim 2 wherein said resilient meanscomprise a helicoidal spring surrounding said rod, said helicoidalspring having one of its ends abutting against said handle and the otherend thereof engaging against the other end of said tubular member.

4. A hand tool for pigtailing a shielded conductor comprising a bulboushandle member having a neck portion projecting away therefrom, said neckportion having an elongated bore extending inwardly from the forward endthereof, an elongated tubular element disposed within said bore andextending forwardly of the forward end of said neck portion, anelongated cylindrical rod, said rod having one of its ends disposedwithin said tubular element coaxially therewith, means fixedly securingsaid one end of said rod to said handle, the other end of said tubularmember extending beyond the tially cylindrical sleeve fixedly secured tothe other end of said tubular element, an elongated substantially hollowtubular member mounted for reciprocation within said sleeve and having apointed outer end, said tubular member having an outwardly turned radialflange at its other end adapted to engage against the inner end of saidsleeeve when said hollow tubular member has been moved to its maximumextended position away from said handle, and a helicoidal springdisposed within said spring abutting against the inner end of said boreand the other end of said spring engaging against said flange, saidspring constantly tending to urge said hollow tubular member formovement towards its maximum extended position.

References Cited in the file of this patent UNITED STATES- PATENTS

